Lane Kiffin promoted Clay Helton to offensive coordinator and announced the hiring of three new assistants. Mike Summers will be offensive line coach, while Tommie Robinson will coach running backs and Mike Ekelar will coach linebackers.

Helton has been the Trojans’ quarterbacks coach the past three seasons. He added the passing game coordinator title in 2012.

Summers spent the past three seasons as Kentucky’s offensive line and running game coordinator. Before Kentucky, he was hired by Bobby Petrino in 2003, and coached with Petrino until 2009 through stops at Lousiville, the Atlanta Falcons and Arkansas. He accepted a position to re-join Petrino at Western Kentucky in January.

Robinson spent the past three seasons as the Arizona Cardinals’ running backs coach. He joined the Cardinals after working the previous three seasons as running backs coach at Miami (Fla.).

Ekeler spent the past two seasons on Kevin Wilson’s staff at Indiana. Before that, he was linebackers coach at Nebraska for three seasons (2008-10).

James Cregg will remain as offensive line coach working alongside Summers, while associate head coach and special teams coordinator John Baxter will add the tight ends to his coaching duties.